#include <stdio.h>

void insert(char* s, char* t, int pos) {
    int sLen = 0;
    int tLen = 0;
    while (s[sLen]!= '\0') {
        sLen++;
    }
    while (t[tLen]!= '\0') {
        tLen++;
    }

    for (int i = sLen + tLen - 1; i >= pos + tLen; i--) {
        s[i] = s[i - tLen];
    }

    for (int i = 0; i < tLen; i++) {
        s[pos + i] = t[i];
    }
    s[sLen + tLen] = '\0';
}

int main() {
    char s[] = "Hello World!";
    char t[] = "Inserted ";
    int pos = 6;
    insert(s, t, pos);
    printf("%s\n", s);
    return 0;
}